Buglyst Blog
Learn to debug under pressure.
Playbooks for fast pattern recognition, guides for the full investigation, and articles for the engineering judgment around the edges.
17 playbooks · 509 guides · 95 articles · 12 linked practice labs ·skip to practice
Fast pattern recognition for the production failures engineers see most often.
17 playbooks
Debugging Env Var Issues
A concise checklist for incidents where local works but CI, staging, or production changes behavior.
Debugging Cache Stampedes
How to recognize and contain request spikes when cached data expires.
Debugging CORS Origin Bugs
A practical way to inspect origin parsing, credentials, and header behavior.
Debugging Retry Bugs
Retry issues often hide the first failure and create duplicate work.
Debugging Timezone Bugs
Time bugs usually live at day boundaries, DST changes, and unit conversions.
Debugging Pagination Bugs
Pagination bugs hide in boundary math, cursor reuse, and new records arriving between pages.
Structured investigations for the failure modes engineers meet in real systems.
Hunting Down Memory Leaks Caused by Improper WeakMap/WeakSet Usage
A practical guide to diagnosing and fixing memory leaks from WeakMap/WeakSet anti-patterns in production JavaScript applications.
Debugging for-await-of Errors with Async Iterators
A senior engineer's guide to diagnosing and fixing for-await-of errors when consuming async iterators, covering common pitfalls like unhandled rejections, premature termination, and generator misconfiguration.
Debugging Unexpected State Changes from JavaScript Object Mutation
A practical guide to identifying and fixing bugs caused by unintended object mutation in JavaScript, with real-world examples and debugging strategies.
Debugging TypeScript 'satisfies' Operator Errors
A practical guide to diagnosing and resolving type errors when using the TypeScript satisfies operator, including narrowing, excess property checks, and type inference pitfalls.
Debugging TypeScript Readonly Property Violations
How to diagnose and fix readonly property violations in TypeScript, including mutation via methods, aliasing, and array/object nesting.
Debugging JavaScript Proxy Reflect Traps: When Your Proxy Silently Fails
Guide to debugging silent failures in JavaScript Proxy traps when using the Reflect API. Covers missing return values, revoked proxies, and infinite recursion.
Long-form thinking on debugging habits, observability, and the systems around the bug.
Debugging Production Issues Without a Debugger: Approaches That Work
Attaching an interactive debugger in production is usually impossible. Here’s how I gather signal, reproduce issues, and restore service using other techniques.
Writing Bug Reports That Developers Appreciate
A good bug report is more than a template. Learn which details actually move the needle, and which common 'best practices' waste developer time.
Assert Statements: Where They Help and Where They Hurt
Assert statements are a double-edged sword. Used correctly, they catch bugs early and document invariants. Used carelessly, they can mask failures and create security holes. Here's how to wield them effectively.
Defensive Logging: Patterns for Surviving Production Data Rot
Most logging advice stops at 'log more'. Here's how to log defensively—handling nulls, encoding, PII, and context propagation before they rot your observability pipeline.
Debuggers vs Console.log: Why I Stopped Using Print Statements for Debugging
Print statements are the duct tape of debugging. They work for trivial issues, but for race conditions, async flows, or deep call stacks, a debugger saves hours. Here's what I learned after years of using both.
Treating Bugs as Hypotheses: How the Scientific Method Fixes Debugging
Frustrated by flailing through logs? The scientific method turns debugging into a reproducible process. Here's how to formulate hypotheses, design experiments, and isolate root causes with confidence.